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1.
叶伟  王健  刘加海 《体育科学》2004,24(9):19-23,66
应用非线性动力学的方法,研究最大和60%MVC强度肱二头肌静态疲劳负荷及其恢复期表面肌电信号复杂度变化规律,探讨肌肉疲劳过程中sEMG信号变化的可能原因和机制。结论:sEMG信号Lempel—Ziv复杂度反映了神经活动策略和神经肌肉功能状态的变化。运动负荷诱发肱二头肌静态疲劳过程中sEMG信号复杂度随运动负荷时间延长而减小,恢复期sEMG信号复杂度和MVC均随恢复时间的延长以相似的模式快速恢复,提示,sEMG信号复杂度可以用于肌肉功能状态恢复的评价。  相似文献   

2.
电刺激诱发胫骨前肌疲劳过程中诱发肌电图的变化特征   总被引:1,自引:0,他引:1  
目的:揭示肌肉疲劳时神经肌肉系统兴奋性的变化规律。方法:以10名健康男子为对象,采用随意性最大的肌肉收缩(V组)和电刺激诱发肌肉收缩(E组)的两种运动形式,对足关节背屈运动过程中的胫骨前肌疲劳前后表面肌电图(sEMG)和诱发肌电图(eEMG)的变化进行比较分析。结果:(1)V组和E组的sEMG的积分值和平均频率均出现了降低的趋势,而且E组的变化较为明显;(2)E组Mmax在肌力下降之前,就出现了明显低下的现象;(3)V组和E组的H/Mmax在肌肉疲劳发生后均出现了低下现象。结论:肌纤维活动电位的异常、神经肌肉接头部传导不全、脊髓运动神经元兴奋性低下等因素的共同作用,是导致肌肉疲劳发生的重要原因。但由于肌肉收缩方式不同而上述变化并不完全一致。  相似文献   

3.
表面肌电信号的检测是一种无创电检测方法,它的检测分析对临床诊断及康复医学,运动医学等具有重要意义。肌肉疲劳产生过程中,肌电图的振幅和频谱指标均会产生相应变化,肌肉疲劳通常是指肌肉运动系统最大做功能力或最大收缩能力暂时下降。SEMG信号可以在一定程度上反映肌肉收缩功能的变化,在运动性肌肉疲劳研究中将发挥重要作用。  相似文献   

4.
肌肉疲劳通常是指肌肉运动系统最大作功能力或者最大收缩能力的暂时下降,表面肌电图信号可以在一定程度上反映肌肉收缩功能的变化,其检测具有非损伤性、实际性、多靶点测量等优点.通过文献综述法简要总结了运动导致肌肉疲劳的表面肌电图特征,介绍了表面肌电图主要测量指标及其影响因素.  相似文献   

5.
表面肌电信号的检测是一种无创电检测方法,它的检测分析对临床诊断及康复医学,运动医学等具有重要意义.肌肉疲劳产生过程中,肌电图的振幅和频谱指标均会产生相应变化,肌肉疲劳通常是指肌肉运动系统最大做功能力或最大收缩能力暂时下降.SEMG信号可以在一定程度上反映肌肉收缩功能的变化,在运动性肌肉疲劳研究中将发挥重要作用.  相似文献   

6.
王翔 《浙江体育科学》2008,30(6):104-106
通过等长背伸运动负荷诱发腰部竖脊肌疲劳并记录全程表面肌电(sEMG)信号,分别以快速傅立叶变换(FFT)计算平均功率频率MPF和非线性RQA方法计算确定性线段百分数(?T)。结果显示,MPF随着肌肉疲劳的发展而逐渐下降,而?T呈现反向变化趋势,提示肌肉疲劳时的sEMG信号规律性在增强。?T的变异系数CV比MPF的小,说明?T作为腰部肌肉功能状态的评价指标具有独特的优势。  相似文献   

7.
运动生理学     
6804.2 20012361sEMG 信号分析及其应用研究进展=Some advancesin the research of sEMG signal analysis and itsapplication[刊,中,A]/王健∥体育科学.-2000.-20(4).-56-60 参 25(TY)肌电图∥肌肉收缩∥肌纤维∥分析∥肌肉∥神经表面肌电信号是从肌肉表面通过电极引导、记录下来的神经肌肉系统活动时的一维时间序列信号,其变化与参与活动的运动单位数量、运动单位活动模式和代谢状态等因素有关,能够实时地、准确地和在非损伤状态下反映肌肉活动状态和功能状态。本文拟就 sEMG 信号分析及其应用研究进展进行系统回顾。  相似文献   

8.
慢性下腰痛患者腰部表面肌电信号的变化特征   总被引:3,自引:1,他引:2  
在中等强度动态等惯性力运动负荷条件下采集腰部L3-L4和L5-S1部位的sEMG信号,采用快速傅立叶变换和定量递归分析与复杂度计算等方法分析研究sEMG信号变化特征,采用主动康复治疗手段观察其对腰部肌肉功能的影响。结果表明:采样部位对各项sEMG分析指标以及被试分组对AEMG的作用无明显统计学意义,而采样时间对各项sEMG分析指标以及被试分组对其它sEMG分析指标的影响均有明显统计学意义。慢性下腰痛患者的sEMG信号具有低频、不复杂和有序的信号特征,主动康复治疗对改善腰部肌肉功能具有明显的作用。  相似文献   

9.
最大等长收缩过程中及恢复期表面肌电信号的变化   总被引:2,自引:0,他引:2  
为了了解sEMG信号在运动诱发的疲劳恢复期内的规律,本研究以肱二头肌持续最大收缩至肌力下降到初始值的50%以及恢复期120秒内不同时刻获得的sEMG信号为研究对象,采用线性和非线性分析方法(FFT和RQA)计算出AEMG、MF和Determ%这些指标以及肌力(MVC)的变化情况。结果发现,在等长收缩过程中,AEMG迅速增加然后呈线性递减,MF从收缩的一开始一直呈现出线性下降的变化模式,而Determ%除了第1个值显著大于第2个外,其余表现出线性递增的变化模式。在恢复期内,AEMG的变化没有明显的规律性,MF随着和Determ%均表现出良好的恢复趋势。MF和Determ%为半时恢复期为12.9和5.2秒,显著低于MVC的19.2秒。在恢复期内没有出现在等长收缩过程中的第1段信号的Determ%大于第2段信号的情形。研究提示,sEMG信号可能更主要受CNS对肌肉控制策略的影响,Determ%的变化可能揭示包含肌肉功能状态的生物学信息。  相似文献   

10.
单侧肢体运动对对侧肌肉肌电频率的影响   总被引:3,自引:1,他引:2  
目的:研究单侧肢体动态运动诱发肌肉疲劳对对侧肌肉肌电信号平均功率频率(MPF)的影响,验证MPF下降的中枢控制作用.方法:10名男性受试者一侧上肢(负荷臂)分别完成5kg持重动态运动负荷实验和无负重放松实验,记录另外一侧(观察臂)完成4kg持重等长运动实验时肱二头肌、肱三头肌和斜方肌的sEMG信号,考察负荷臂两种运动状态下观察臂肌肉肌电的MPF、平均肌电值、复杂度和有序性等变化的差异性.结果:5kg持重动态运动实验过程中观察臂肱二头肌、肱三头肌和斜方肌的MPF均值均显著低于无负重放松实验状态;肱三头肌MPF的下降斜率显著增加.结论:负荷臂动态运动诱发一侧肌肉疲劳过程中可以造成对侧观察臂肌肉平均功率频率产生伴随性变化,表明sEMG信号活动具有确切的中枢控制成分.  相似文献   

11.
This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue.  相似文献   

12.
The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae.  相似文献   

13.
本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。  相似文献   

14.
重新认识体育的社会关联   总被引:3,自引:1,他引:2  
体育与政治之间存在一个悖论,体育的发展与经济实力之间没有直线相关,体育与教育部分重叠,体育与宗教最为近缘,体育可借用科学手段,体育的艺术禀性日益明显,体育与养生反映着两种人生观。  相似文献   

15.
对全面把握游泳训练环节的探讨   总被引:4,自引:0,他引:4  
从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。  相似文献   

16.
我国体育市场管理法规研究   总被引:12,自引:0,他引:12  
采用调查法和比较法对全国体育市场立法和管理现状进行调查,对部分较早出台并有一定代表性的省市的体育市场管理法规的立法和管理情况进行了研究,提出了体育市场管理立法和管理的原则、基本程序、措施及其一般模式,为规范全国体育市场管理提供参考依据。  相似文献   

17.
本文运用文献资料法,逻辑分析法,在遵循逻辑学、哲学、心理学原理的前提下,对竞技健美操技术的概念进行了界定,对竞技健美操技术进行了分类研究,在此基础上分析了竞技健美操技术的结构,为系统、科学的组织竞技健美操的教学和训练提供理论上的参考,为促进竞技健美操理论体系的完善和协调发展做出一定的贡献。  相似文献   

18.
结合欧洲足球技战术的发展特点,就鲁能泰山足球队的体能训练、技术训练、防守阵型、进攻方式、定位球、职业态度、球星培养等诸方面所存在的不足进行了分析,提出相应的改进意见。  相似文献   

19.
本文运用文献资料法、历史法、因素分析等方法,从体育考古学的角度对古滇国主要墓葬群出土文物进行深入研究.研究表明:古滇文化已具备体育文化构建因子,滇国在重大节日举行的斗牛、竞渡、磨秋、剽牛祭祀等民俗活动中已彰显出体育的特色,是古滇民族主要的民俗体育活动形式.古滇人民观念不羁、思想无垠,演绎了独具特色的古滇民俗体育文化,是我们中华民族灿烂辉煌的体育文化中的一支奇葩.  相似文献   

20.
Capoeira could be defined as a Brazilian martial art and game to be played. This research explored how capoeira play might be considered to facilitate connectedness amongst newly-recruited persons, plus any other ramifications of capoeira involvement. A beginners’ course of capoeira was provided to participants, free of charge, in an English city in the West Midlands—new capoeiristas in a new venue for capoeira. Researchers attended classes to collect/construct overt non-participant observation data. In addition, semi-structured interviews were undertaken with the new capoeiristas post-course. This article explores researchers’ observation fieldnotes and interviewees’ narratives. These qualitative data-driven debates include the concepts: self, identity, escapism, multiparty endeavour, community, temporality, enjoyment, and transcending boundaries. Capoeira is theorised in a fresh manner that highlights social benefits of capoeira—for example as an enjoyable and supportive group endeavour which includes elements of social play and community-building—plus benefits for self that can transcend the boundaries of the class. Findings highlight how capoeira can be considered an inherently multiparty endeavour whereby social actors form, and experience, a community in order to embrace capoeira play. Data suggest capoeira can facilitate group playfulness, joviality, and laughter. Further, capoeiristas can enact and experience—some mode of—escapism via capoeira, whereby new place and pursuit can facilitate hedonistic diversion from the mundane. Capoeira appears to provide adventure and liberation into a relatively unburdened part of, or place in, social life. Corporeal and discursive boundary-empowerment can also be experienced by capoeiristas, fostering positive identity work in the wider world. Capoeira can be argued to facilitate mutuality (e.g. community experience and group work) and egoism (e.g. an individual's identity work) concurrently. This research suggests that modified capoeira for beginners can be beneficial for both the new capoeiristas themselves and for positive community action during and beyond class.  相似文献   

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